title: Differential roles of the prefrontal cortical subregions and basolateral amygdala in compulsive cocaine seeking and relapse after voluntary abstinence in rats.
abstract: Compulsive drug use and a persistent vulnerability to relapse are key features of addiction. Imaging studies have suggested that these features may result from deficits in prefrontal cortical structure and function, and thereby impaired top-down inhibitory control over limbic-striatal mechanisms of drug-seeking behaviour. We tested the hypothesis that selective damage to distinct subregions of the prefrontal cortex, or to the amygdala, after a short history of cocaine taking would: (i) result in compulsive cocaine seeking at a time when it would not usually be displayed; or (ii) facilitate relapse to drug seeking after abstinence. Rats with selective, bilateral excitotoxic lesions of the basolateral amygdala or anterior cingulate, prelimbic, infralimbic, orbitofrontal or anterior insular cortices were trained to self-administer cocaine under a seeking-taking chained schedule. Intermittent mild footshock punishment of the cocaine-seeking response was then introduced. No prefrontal cortical lesion affected the ability of rats to withhold their seeking responses. However, rats with lesions to the basolateral amygdala increased their cocaine-seeking responses under punishment and were impaired in their acquisition of conditioned fear. Following a 7-day abstinence period, rats were re-exposed to the drug-seeking environment for assessment of relapse in the absence of punishment or cocaine. Rats with prelimbic cortex lesions showed decreased seeking responses during relapse, whereas those with anterior insular cortex lesions showed an increase. Combined, these results show that acute impairment of prefrontal cortical function does not result in compulsive cocaine seeking after a short history of self-administering cocaine, but further implicates subregions of the prefrontal cortex in relapse.
authors.affiliation: Institut de Neuroscience de la Timone, UMR 7289 CNRS, Université d'Aix-Marseille, 27 Bld Jean Moulin, 13385 Marseille, France. yann.pelloux@univ-amu.fr
authors.forename: Yann
authors.initials: Y
authors.lastname: Pelloux
authors.affiliation: Department of Psychology, University of Cambridge, Downing St, CB2 3EB, Cambridge, UK.|Behavioural and Clinical Neuroscience Institute, University of Cambridge, Downing St, CB2 3EB, Cambridge, UK.
authors.forename: Jennifer E
authors.initials: JE
authors.lastname: Murray
authors.affiliation: Department of Psychology, University of Cambridge, Downing St, CB2 3EB, Cambridge, UK.|Behavioural and Clinical Neuroscience Institute, University of Cambridge, Downing St, CB2 3EB, Cambridge, UK.
authors.forename: Barry J
authors.initials: BJ
authors.lastname: Everitt
mesh_terms: D000818:Animals; D021461:Animals, Outbred Strains; D066272:Basolateral Nuclear Complex / Q000187:drug effects / Q000503:physiopathology*; D003042:Cocaine / Q000008:administration & dosage; D019970:Cocaine-Related Disorders / Q000503:physiopathology*; D003213:Conditioning, Psychological / Q000502:physiology; D018765:Dopamine Uptake Inhibitors / Q000008:administration & dosage; D058999:Drug-Seeking Behavior / Q000187:drug effects / Q000502:physiology*; D004597:Electroshock; D005239:Fear / Q000502:physiology; D046352:Freezing Reaction, Cataleptic / Q000502:physiology; D008297:Male; D009042:Motivation / Q000187:drug effects / Q000502:physiology; D017397:Prefrontal Cortex / Q000187:drug effects / Q000503:physiopathology*; D051381:Rats; D012008:Recurrence; D012646:Self Administration
chemical_list: D018765:Dopamine Uptake Inhibitors; D003042:Cocaine
keywords: cocaine self-administration; compulsivity; prefontal cortex; relapse; top-down inhibitory control